Judging from appearances, Mr. Sakurauchi's meetings with President Reagan, Secretary of State Alexander M. Haig Jr., and other top officials have been most cordial. In a speech to the Japan-American Society of Washington, prepared for delivery March 23, the Japanese foreign minister said that his talks here had been ''very fruitful.''

Privately, however, other Japanese officials spoke in frustration and even anger of pressures from the United States, which they consider to be based on faulty analysis. They say that the Reagan administration is trying to make Japan a ''scapegoat'' for America's economic troubles. And, in effect, they say that Japan is already doing about all that it can to open up its markets.

American calls for a substantial reduction in Japan's nontariff trade barriers are at the root of the latest rise in tensions between the US and Japan. US Commerce Secretary Malcolm Baldrige has denied that he is issuing any ultimatums. But at the same time he has said when it comes to the trade issue, ''time is running out.''

Mr. Baldrige has also warned that he would have to support restrictions imposed by the US Congress on Japanese imports if Japan does not further open its markets to American exports.

A Japanese official says that in a meeting with Foreign Minister Sakurauchi on March 22, Treasury Secretary Donald T. Regan made it clear that the White House felt it had a serious problem with Congress over Japanese trade. According to this official, Mr. Regan said that it was essential that Japan improve the situation before the seven major industrialized nations hold their next summit meeting in France in early June.

What may be unusual in all this is not the longstanding disagreement between the two sides but, as has already been observed in a recent article from Tokyo in The Wall Street Journal, the outspokenness of the Japanese reaction. It is not the Japanese style to be blunt. But in his March 23 speech, Foreign Minister Sakurauchi said that some of the American charges concerning the ''closed'' Japanese market are ''based on outdated conceptions about Japan.''

''I cannot agree with the view that the United States' trade deficit with our country is caused primarily by the 'closedness' of the Japanese market,'' the foreign minister said.

Another Japanese official says that the most significant reasons for the US-Japanese trade imbalance were Japan's superior productivity, its good labor-management relations, and insufficient efforts by American businessmen to penetrate Japanese markets.

The official says that in his meeting with Treasury Secretary Regan, Foreign Minister Sakurauchi emphasized the need for the US to help revitalize the world economy and to lower its high interest rates.

For some time, the Japanese have complained privately about American interest rates. They are now becoming more open in their criticism on that issue.

The official says that the Japanese people have shown a growing willingness to cooperate with the US on a number of issues, including increased Japanese defense spending. He noted that on the issues of Poland and Afghanistan, Japan stood by the US. But he says that should Japan continue to be blamed for economic problems in the US and Europe, it may begin to slow such cooperative efforts.

In defending their efforts to open Japan's markets, Japanese officials note, among other things, that their government has announced that 67 trade barriers would be reduced and that an ombudsman office to handle complaints from foreign businessmen has been established.

In recent testimony before a Senate subcommittee, however, Lionel H. Olmer, undersecretary for international trade at the US Commerce Department, said despite the moves Japan has made, ''little has happened in a practical way.'' He said that of the 67 measures taken, five were counted twice, 19 had been handled previously, 10 were individual product problems, and only nine or 10 appeared to have immediate significance.